help with drobo to drobo sync

so here is my situation.

I have purchased 2 droboFS’s each with a few TB of space in them one for my mother’s house for her file server and one for my house for my file server. I have created shares for each of us on each Drobo and have a full copy of each of our files on the respective shares.

What I would like to do now is setup a remote synchronization of the two units first setup locally and then extended to over the internet once the system is setup.

I was thinking about using rsync but I’m willing to do anything but would prefer to not use computers in the backup process if possible.

Any ideas would be appreciated.


Rsync is the way to go. Just make sure you use SSH for the transport. In fact, the worst part of the rsync setup is making sure the routers are properly configured to allow port forwarding.

thanks. actually when I talked to support they warned me against it as they said they have seen it cause data loss but I kinda call BS on that.

Well, it can happen if you are not careful with which options you chose when setting up rsync (in particular, be careful with the --delete stuff), but other than that, I’m pretty sure rsync is as bug-free as their software, if not more.

Hi Newhorizon,
I do this exact same thing with two drobos. You don’t need to use an intermediate computer, you can rsync from one machine to another.

Ricardo is right, rsync over SSH is the way to go. Here’s the steps you want to do.

  1. Install OpenSSH (the real one, not the dropbear version).
    1a. Set a STRONG root password (at least 128 bits of entropy). Remember, this server will now be facing the outside world.
  2. Install Rsync.
  3. Install screen (important!)
  4. Write a script so that every time your drobo re-boots, the default password gets re-written with your strong one. Make sure your have you password written down, otherwise you’re boned.
  5. Configure your router. I STRONGLY suggest that you don’t use the default port (22). Most routers will allow you to re-route a different port. IE, your external port can be 2345, the router will send all packets to port 22.
  6. Repeat steps 1-5 on the second drobo.
  7. (optional) set up some SSH-RSA keys between each of the drobos, so you can skip the passwords for rsyncing.

Okay, you’re all good to go. To go:

  1. SSH into your local drobo.
  2. Run screen.
  3. Start your rsync backup. It should look something like this:
    rsync -aviPh --progress --delete-after -e ‘ssh -p 2345’ --rsync-path=/mnt/Drobo-FS/Shares/DroboApps/rsync/rsync /mnt/Drobo-FS/Shares/Backup/
  4. Detach your screen (ctrl-a d) (to get back into a detached session start screen with ‘screen -R -D’)
  5. Exit out of your ssh session and sleep easy.

I hope this was of help to you. If you get stuck on any of these steps, please feel free to drop a line.

thanks for that I just have one more simple question. which file do you edit to modify the openssh password? Or do I have to install via with a bit of a dropbear switch like I have read elsewhere on these boards?

OpenSSH just uses the system password file, not its own, like some of the programs do.

To modify the root password, just log onto the server and use the command ‘passwd’

thanks… turns out I was just being stupid and not logging in with the User@ip and it was just grabbing my system user account and causing issues I think.

a few more questions on this… :slight_smile:

I’m starting to think that some of the problems I’m having are due to the new version of openssl that I installed.

$ ssh
PRNG is not seeded

Also when I try and execute screen I get the following error

$ ./screen-4.0.3
Cannot make directory ‘/tmp/uscreens’: Permission denied

(once again sorry about being a n00b)


it seems like openssl is having trouble getting random data for the key generation process if I read that right.

to execute programs like rsync from anywhere in the shell do I need to create a soft link to the executable in the /usr/bin folder?

if so would it look like

ln -s /usr/bin/rsync /mnt/Drobo-FS/Shares/DroboApps/rsync/rsync

rsync -aviPh --progress --delete-after -e ‘ssh’ --rsync-path=/mnt/Drobo-FS/Shares/DroboApps/rsync/rsync /mnt/Drobo-FS/Shares/Backup2/ Admin@

any insight?

btw just a thought…
careful with auto synchronising…

eg, if your mom deletes some files by mistake, do you really need those deletions synchronised on your server too? :slight_smile: